US4344353A - Hammer - Google Patents
Hammer Download PDFInfo
- Publication number
- US4344353A US4344353A US06/264,495 US26449581A US4344353A US 4344353 A US4344353 A US 4344353A US 26449581 A US26449581 A US 26449581A US 4344353 A US4344353 A US 4344353A
- Authority
- US
- United States
- Prior art keywords
- hammer
- motive fluid
- bias
- fluid flow
- valve
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
- 239000012530 fluid Substances 0.000 claims abstract description 110
- 230000033001 locomotion Effects 0.000 claims description 19
- 238000004891 communication Methods 0.000 claims description 9
- 238000013022 venting Methods 0.000 claims 1
- 230000001351 cycling effect Effects 0.000 abstract description 2
- 230000002093 peripheral effect Effects 0.000 description 7
- 239000011435 rock Substances 0.000 description 3
- 230000015572 biosynthetic process Effects 0.000 description 2
- 238000010276 construction Methods 0.000 description 2
- 230000000149 penetrating effect Effects 0.000 description 2
- 230000000750 progressive effect Effects 0.000 description 2
- 230000003252 repetitive effect Effects 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 230000003466 anti-cipated effect Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 238000005266 casting Methods 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 125000004122 cyclic group Chemical group 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 238000005553 drilling Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005065 mining Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000005381 potential energy Methods 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01B—MACHINES OR ENGINES, IN GENERAL OR OF POSITIVE-DISPLACEMENT TYPE, e.g. STEAM ENGINES
- F01B11/00—Reciprocating-piston machines or engines without rotary main shaft, e.g. of free-piston type
- F01B11/04—Engines combined with reciprocatory driven devices, e.g. hammers
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
- F01L17/00—Slide valve-gear or valve arrangements with cylindrical, sleeve, or part annularly-shaped valves surrounding working cylinder or piston
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
- F01L25/00—Drive, or adjustment during the operation, or distribution or expansion valves by non-mechanical means
- F01L25/02—Drive, or adjustment during the operation, or distribution or expansion valves by non-mechanical means by fluid means
- F01L25/04—Drive, or adjustment during the operation, or distribution or expansion valves by non-mechanical means by fluid means by working-fluid of machine or engine, e.g. free-piston machine
- F01L25/06—Arrangements with main and auxiliary valves, at least one of them being fluid-driven
- F01L25/066—Arrangements with main and auxiliary valves, at least one of them being fluid-driven piston or piston-rod being used as auxiliary valve
Definitions
- prior impactors have been those in which a fluid or mechanical spring bias means acts continuously upon the rearward or upstroke end of the hammer piston to provide motive force for driving the hammer piston through its power stroke to impact.
- Such impactors typically rely upon motive fluid pressure applied to the forward end of the hammer piston to upstroke or "cock" the piston against the continuously applied force of the spring bias means thus storing energy in the spring.
- the motive fluid pressure is then exhausted to release the hammer piston whereupon the energy stored in the spring drives the hammer piston through its power stroke to impact.
- This upstroking and releasing of the hammer piston is repeated to provide a relatively rapid succession of impact blows to the work object. If the impact blows are generated with sufficient frequency the apparatus may be employed as an impact drilling device.
- the present invention contemplates various improvements over such known impactors including, but not limited to, improved hammer piston reciprocation wherein an actuator valve means is operable under the cooperating impetus of motive fluid pressure and the force of a spring bias means to direct motive fluid flow for actuating a motive fluid inlet and exhaust valve means.
- operation of the actuator valve means is influenced by the effect of the hammer piston upon the spring bias means as energy is alternately stored in and released from the spring bias means during the repetitive hammer piston upstrokes and impact strokes.
- the motive fluid pressure exerts an influence upon the magnitude of the potential energy stored in the spring bias means through its action upon the actuator valve means.
- the present invention thus provides for novel modes of cooperation between motive fluid pressure, a spring bias means, hammer piston, actuator valve, and a motive fluid inlet and exhaust valve means in an impactor apparatus, and an improved means of hammer piston cycling in such an apparatus.
- FIG. 1 is a central longitudinal section of an impactor apparatus constructed according to the principles of the present invention.
- FIGS. 2 through 5 inclusive are central longitudinal sections similar to FIG. 1 showing the impactor apparatus at progressive stages of piston reciprocation through a cycle of impactor operation.
- FIG. 1 There is generally indicated at 10 in FIG. 1 an impactor apparatus constructed according to one preferred embodiment of the instant invention and shown as including a body assembly 12 comprised of a rigid, formed main casing member 14, a machined steel casting for example, disposed axially intermediate a front head 16 and a backhead 18.
- a plurality of elongated side rods 20 extend longitudinally throughout the length of body assembly 12 and are suitably threaded adjacent their opposite longitudinal ends to receive respective threaded nuts 22 thereon which are tightened down upon front head 16 and backhead 18 to rigidly, releasably secure casing 14 therebetween as shown.
- Casing 14 includes a pair of elongated and preferably parallel, generally cylindrical bores 24, 26 extending from the rearward end thereof.
- Bore 24 is a stepped through bore which is coaxially aligned with a respective through bore 28 formed in front head 16, and bore 26 preferably is a blind bore extending from the rearward end of casing 14.
- Bores 24, 26 are sealingly closed adjacent their respective rearward ends by backhead 18 as shown.
- Bore 24 has disposed therewithin an elongated, generally annular, stepped sleeve or bushing member 30 within which a body portion 34 of a stepped cylindrical hammer piston 32 is axially slideable in such manner that an elongated, forwardly projecting stem portion 36 of hammer 32 may be closely slideably received within an intermediate, reduced diameter portion 38 of bore 24.
- Bushing 30 also accommodates within an enlarged diameter interior portion 40 thereof a generally annular, elongated sleeve valve member 42 which is slideably disposed for axial movement between motive fluid inlet and exhaust positions as will be described hereinbelow.
- a stepped cylindrical striking bar 44 which includes a rearwardly projecting stem portion 46 that may be slideably received within bore portion 38 such that during impactor operation hammer 32 may be reciprocated for repetitive impact of stem portion 36 upon the striking bar stem 46 either through direct mechanical impact or through transmission of impact forces through a fluid column trapped within the bore portion 38 between the spaced apart end portions of the hammer and the striking bar stems 36, 46.
- a generally annular, elongated sleeve or bushing 48 having a stepped, cylindrical inner periphery which axially, slideably accommodates therewithin a generally stepped cylindrical piston valve element 50.
- a fluid inlet passage 52 formed within casing 14 includes an annular passage portion 53 which encompasses bushing 30 to communicate with a fluid inlet port means 54 preferably formed as a plurality of circumferentially spaced ports which radially penetrate bushing 30 to communicate between the inlet passage 52 and valve member 42.
- an exhaust fluid passage 56 formed within casing 14 and preferably including an enlarged exhaust fluid receiving chamber 57, communicates with a plurality of circumferentially spaced fluid exhaust ports 58 which radially penetrate bushing 30 forwardly of inlet ports 54.
- Sleeve valve 42 includes a plurality of circumferentially spaced radially extending ports 60 located such that at the extreme rearward and forward axial positions of the valve 42, ports 60 therein cooperably register, respectively, with inlet and exhaust ports 54, 58 to provide selective communication of the space forwardly of piston body 34 (hereinafter designated space 62) with either the fluid inlet or exhaust passages 52, 56.
- a suitable hydraulic motive fluid circuit includes a pump which communicates via a suitable fluid flow conduit 66 with inlet passage 52 by way of a port 68 penetrating the outer wall of the casing 14 and including any suitable, conventional connection means (not shown) for connection of conduit 66 thereto.
- exhaust chamber 57 communicates by way of a suitable conduit 70 with a reservoir R which receives exhaust fluid from impactor 10.
- Pump 64 is maintained in fluid flow communication with reservoir R via a conduit 72 to draw supply fluid therefrom.
- both hammer 32 and piston valve 50 cooperate with fluid inlet and exhaust passages 52, 56 to provide for flow of actuating motive fluid to the axially opposite ends of sleeve valve 42 for cyclic operation of valve 42 as follows.
- a through opening 74 penetrates the forwardmost end of bushing 48 whereby motive fluid pressure is continuously supplied from inlet 52 to a forward end surface 76 of piston valve 50.
- a fluid supply passageway means 78 for delivery of actuating fluid pressure to the forward end of sleeve valve 42 as follows.
- a first segment 78a of passageway means 78 is defined in piston valve 50 by a coaxial blind bore 80 extending from forward end 76 and communicating by way of a plurality of circumferentially spaced and radially extending passages 82 with a respective plurality of circumferentially spaced, longitudinally extending grooves 84 formed in the external periphery of piston valve 50. As shown in FIG.
- grooves 84 communicate with a second passageway segment 78b which includes a circumferential groove 86 formed about an inner peripheral portion of bushing 48 and communicating by way of one or more circumferentially spaced passages 88 which radially penetrate bushing 48, with a similar, circumferentially extending peripheral groove 90 formed in the outer periphery of bushing 48.
- Passageway segment 78b further includes at least one passage 92 which communicates with yet another peripheral groove 94 formed in the periphery of bore 24.
- a final passageway segment 78c includes a generally radially and longitudinally extending flow passage 96 communicating adjacent one end thereof with groove 94 and adjacent the opposite end thereof with a plurality of circumferentially spaced ports 98 which radially penetrate a forward end portion of bushing 30 to communicate with the forward end of valve 42 to complete supply passageway 78.
- the passageway segment 78c also serves to connect the forward end of valve 42 with exhaust chamber 57 by way of passage 96, groove 94 and an exhaust passageway means 100 including a first passage segment 100a comprised of a plurality of circumferentially spaced passages 102 which radially penetrate bushing 30 at such locations therein that during predetermined portions of the impactor operating cylce passages 102 communicate by way of a peripheral groove 104 within the interior of bushing 30 with a second passage segment 100b including a plurality of circumferentially spaced and longitudinally extending grooves 106 formed in the periphery of hammer body 34.
- Grooves 106 in turn, communicate with another peripheral groove 108 and cooperating passages 110 radially penetrating sleeve 30, and passages 110 communicate with a flow network of circumferentially extending peripheral grooves such as indicated at 112, 114 and cooperating passages such as 116 similar in many respects to the construction of the various flow passages described hereinabove.
- Circumferential groove 114 communicates by way of an elongated passage 115 with chamber 57 to provide for fluid flow thereto from the forward end of valve 42 as will be described hereinbelow.
- Means are also provided to supply and evacuate motive fluid to and from the rearward end of sleeve valve 42 as follows.
- grooves 106 in hammer body 34 provide fluid communication between the rearward end of the valve 42 and groove 108 whereby motive fluid may be exhausted from the rear of valve 42 to chamber 57 by way of exhaust passage segment 100b described hereinabove.
- the hammer 32 is so positioned that grooves 106 are isolated from the rear of valve 42, and the forward edge of hammer body portion 34 exposes the rear of valve 42 to inlet fluid pressure within space 62 as will be described hereinbelow.
- a spring bias means in the form of a fluid pressure accumulator 120 is provided by the interior spaces within each of the bushings 30, 48 intermediate backhead 18 and, respectively, hammer 32 and piston valve 50. These interior spaces are joined for fluid communication by a generally transverse opening 118 communicating therebetween through rearward end portions of bushings 30, 48 and the intervening portion of casing 14.
- Accumulator 120 is provided with fluid charging and discharging means such as a port 122 which penetrates backhead 18 to communicate between the exterior environment and accumulator 120.
- port 122 may include a fluid tight sealed closure such as a plug 124 releasably secured therein to permit charging or release of pressurized gas.
- plug 124 may be replaced by a fluid conduit connection to connect accumulator 120 to a pressurized gas supply such as a gas bottle 126 as shown schematically.
- a pressurized gas supply such as a gas bottle 126 as shown schematically.
- an accumulator gas precharge for example approximately 1200 psi (although a substantially greater or lesser precharge may also suffice) is maintained within accumulator 120 during impactor operation.
- the impactor structure described hereinabove is operable as follows. Initially in the cycle, with reference to FIG. 1, hammer 32 if at rest in its forwardmost position, having delivered an impact blow to striking bar 44. During the downstroke, exhaust ports 58 were open to chamber 57 whereby fluid in space 62 was directed to the chamber 57. Likewise, ports 54 were closed whereby supply fluid pressure in inlet 52 was cut off from space 62. Piston valve 50 is in its forwardmost position. The continuous application of motive fluid pressure to the forward end 76 of piston valve 50 displaces piston 50 to the left against the bias of the gas precharge contained within accumulator 120 thus compressing the gas and storing additional energy in accumulator 120. Piston valve 50 is progressively displaced to a position (FIG.
- Valve 42 is thus displaced toward its extreme rearward position (to the left as shown) whereat exhaust ports 58 are closed and inlet ports 54 are open to permit motive fluid flow via passage 52 into space 62.
- the space rearwardly thereof communicates by way of grooves 106 in hammer body 34 through the remainder of passage segment 100b with chamber 57 whereby any fluid behind valve 42 is vented to reservoir R.
- the motive fluid pressure supplied by way of the ports 54 into space 62 is effective to retract or upstroke the hammer 32 against the bias of accumulator 120.
- a differential area is provided between the opposite longitudinal ends of the piston valve 50, the rearward end thereof being the larger, whereby equal pressures acting on the opposite ends will provide a net force to the right such that the progressive upstroking of the hammer 32 results in concomitant motion of piston valve 50 to the right.
- the differential area requires a stepped diameter within bushing 48 to accommodate movement of piston valve 50.
- the variable volume space 128 thus formed is vented to chamber 57 via an extension 115' of passage 115.
- the forward end portion of hammer body 34 isolates the rearward end of sleeve valve 42 from motive fluid pressure.
- the hammer piston upstroke progresses the hammer body portion 34 ultimately exposes the rearward end of sleeve valve 42 to the motive fluid pressure within space 62 (FIG. 4) such that sleeve valve 42 begins once again to move to the right inasmuch as the forward end thereof now communicates with exhaust chamber 57 via passages 96, 100a, and 100b, as described hereinabove.
- sleeve valve 42 moves rightward it begins to close inlet ports 54 and subsequently opens exhaust ports 58 as the hammer piston momentum continues the hammer upstroke.
- sleeve valve 42 ultimately is fully opened to vent fluid pressure within space 62 to chamber 57 and the rearward motion of hammer 32 is terminated.
- Hammer 32 thus begins its downstroke or impact stroke as it is driven forcefully by the bias of the pressurized gas within accumulator 120 to impact.
- the motive fluid pressure applied continuously to the forward end 76 of piston valve 50 begins to move piston valve 50 to the left once again against the gas pressure in accumulator 120 to repeat the impactor operating cycle.
- the hammer piston upstroke portion of the cycle may take up to 80% or more of the cycle time, and the impact blow rate may therefore be readily increased by increasing the pump flow rate to reduce the duration of the relatively long upstroke cycle portion.
- the result is greater impact rate (blows per minute) at a constant blow energy.
- Blow energy may be altered independently of any change in the impact blow rate by increasing or decreasing the gas precharge in accumulator 120. Of course, this may also necessitate an increase in the maximum available motive fluid supply pressure.
- One feature of the described impactor embodiment is that hammer 32 and piston valve 50 move in opposite directions during the hammer piston downstroke. Piston valve 50 thus tends to counteract some of the reaction forces of the hammer movement which would otherwise be absorbed by the operator or the impactor mountings.
- passage segments 78a, b, c and 100a, b) may be modified and varied within a wide design latitude of functional equivalents; hammer 32 and piston valve 50 may be arranged in coaxial alignment with the accumulator 120 and other suitable spring bias means may be disposed therebetween; the spring bias means need not necessarily be a linear spring means; and the like.
Abstract
Description
Claims (19)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US06/264,495 US4344353A (en) | 1979-05-14 | 1981-05-18 | Hammer |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US3905179A | 1979-05-14 | 1979-05-14 | |
US06/264,495 US4344353A (en) | 1979-05-14 | 1981-05-18 | Hammer |
Related Parent Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US3905179A Continuation | 1979-05-14 | 1979-05-14 |
Publications (1)
Publication Number | Publication Date |
---|---|
US4344353A true US4344353A (en) | 1982-08-17 |
Family
ID=26715779
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US06/264,495 Expired - Fee Related US4344353A (en) | 1979-05-14 | 1981-05-18 | Hammer |
Country Status (1)
Country | Link |
---|---|
US (1) | US4344353A (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20120260794A1 (en) * | 2011-03-01 | 2012-10-18 | Tonand Brakes Inc. | Passive piston unit |
Citations (16)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2559478A (en) * | 1948-11-22 | 1951-07-03 | Stonefield Inc | Hydraulic impact tool |
US2861486A (en) * | 1955-05-13 | 1958-11-25 | Langenstein & Schemann A G | Hydraulically actuated drop hammer |
US3045768A (en) * | 1958-07-14 | 1962-07-24 | Gardner Denver Co | Fluid operated percussion drill |
US3060894A (en) * | 1960-02-29 | 1962-10-30 | Ingersoll Rand Co | Rock drill |
US3456741A (en) * | 1967-07-05 | 1969-07-22 | Sonomotive Eng Ltd | Percussive tools and machines |
US3460636A (en) * | 1967-07-05 | 1969-08-12 | Sonomotive Eng Ltd | Percussive tools and machines |
US3487752A (en) * | 1967-07-05 | 1970-01-06 | Sonomotive Eng Ltd | Percussive tools and machines |
US3552269A (en) * | 1968-03-27 | 1971-01-05 | Krupp Gmbh | Hydraulically operable linear motor |
US3642076A (en) * | 1970-07-17 | 1972-02-15 | Bell Telephone Labor Inc | Impulse-reaction propulsion cycle for mole |
US3739863A (en) * | 1971-06-02 | 1973-06-19 | M Wohlwend | Reciprocating linear hydraulic motors |
US3800664A (en) * | 1971-02-10 | 1974-04-02 | Dobson Park Ind | Impact tools or apparatus |
US3866690A (en) * | 1972-09-25 | 1975-02-18 | Technology Inc Const | Hydraulically powered impact device |
US3872934A (en) * | 1973-10-30 | 1975-03-25 | Nippon Pneumatic Mfg | Impact tool |
US3925985A (en) * | 1973-01-09 | 1975-12-16 | Rapidex Inc | Impact actuator |
US4062268A (en) * | 1974-06-11 | 1977-12-13 | Joy Manufacturing Company | Fluid operable hammer |
US4089252A (en) * | 1977-01-21 | 1978-05-16 | Applied Power, Inc. | Proportional force amplifier |
-
1981
- 1981-05-18 US US06/264,495 patent/US4344353A/en not_active Expired - Fee Related
Patent Citations (16)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2559478A (en) * | 1948-11-22 | 1951-07-03 | Stonefield Inc | Hydraulic impact tool |
US2861486A (en) * | 1955-05-13 | 1958-11-25 | Langenstein & Schemann A G | Hydraulically actuated drop hammer |
US3045768A (en) * | 1958-07-14 | 1962-07-24 | Gardner Denver Co | Fluid operated percussion drill |
US3060894A (en) * | 1960-02-29 | 1962-10-30 | Ingersoll Rand Co | Rock drill |
US3456741A (en) * | 1967-07-05 | 1969-07-22 | Sonomotive Eng Ltd | Percussive tools and machines |
US3460636A (en) * | 1967-07-05 | 1969-08-12 | Sonomotive Eng Ltd | Percussive tools and machines |
US3487752A (en) * | 1967-07-05 | 1970-01-06 | Sonomotive Eng Ltd | Percussive tools and machines |
US3552269A (en) * | 1968-03-27 | 1971-01-05 | Krupp Gmbh | Hydraulically operable linear motor |
US3642076A (en) * | 1970-07-17 | 1972-02-15 | Bell Telephone Labor Inc | Impulse-reaction propulsion cycle for mole |
US3800664A (en) * | 1971-02-10 | 1974-04-02 | Dobson Park Ind | Impact tools or apparatus |
US3739863A (en) * | 1971-06-02 | 1973-06-19 | M Wohlwend | Reciprocating linear hydraulic motors |
US3866690A (en) * | 1972-09-25 | 1975-02-18 | Technology Inc Const | Hydraulically powered impact device |
US3925985A (en) * | 1973-01-09 | 1975-12-16 | Rapidex Inc | Impact actuator |
US3872934A (en) * | 1973-10-30 | 1975-03-25 | Nippon Pneumatic Mfg | Impact tool |
US4062268A (en) * | 1974-06-11 | 1977-12-13 | Joy Manufacturing Company | Fluid operable hammer |
US4089252A (en) * | 1977-01-21 | 1978-05-16 | Applied Power, Inc. | Proportional force amplifier |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20120260794A1 (en) * | 2011-03-01 | 2012-10-18 | Tonand Brakes Inc. | Passive piston unit |
US9091283B2 (en) * | 2011-03-01 | 2015-07-28 | Tonand Brakes Inc. | Passive piston unit |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: CONSOLIDATED TECHNOLOGIES CORPORATION 5070 OAKLAND Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:JOY MANUFACTURING COMPANY A PA CORP;REEL/FRAME:004447/0934 Effective date: 19840717 |
|
FEPP | Fee payment procedure |
Free format text: MAINTENANCE FEE REMINDER MAILED (ORIGINAL EVENT CODE: REM.); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY |
|
LAPS | Lapse for failure to pay maintenance fees | ||
STCH | Information on status: patent discontinuation |
Free format text: PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362 |
|
FP | Lapsed due to failure to pay maintenance fee |
Effective date: 19860817 |
|
AS | Assignment |
Owner name: FIRST COLORADO BANK & TRUST, COLORADO Free format text: SECURITY INTEREST;ASSIGNOR:CONSOLIDATED TECHNOLOGIES CORP., 5070 OAKLAND, DENVER, CO. 80239;REEL/FRAME:005250/0526 Effective date: 19890322 |
|
AS | Assignment |
Owner name: FM INDUSTRIES, INC., TEXAS Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:CONSOLIDATED TECHNOLOGIES CORP.;REEL/FRAME:005305/0101 Effective date: 19900413 |
|
AS | Assignment |
Owner name: BARCLAYS BUSINESS CREDIT, INC., 3811 TURTLE CREEK Free format text: SECURITY INTEREST;ASSIGNOR:FM INDUSTRIES, INC., A CORP. OF TEXAS;REEL/FRAME:005539/0552 Effective date: 19900412 |
|
AS | Assignment |
Owner name: FM INDUSTRIES, INC., TEXAS Free format text: CHANGE OF NAME;ASSIGNOR:FM ACQUISITION CORPORATION;REEL/FRAME:007894/0996 Effective date: 19890405 |